The present invention relates to couplers for casting in a concrete wall of a subterranean vessel, the coupler being for slidably receiving a pipe therethrough and for coupling the pipe to the subterranean vessel.
It is common to cast couplers or pipe seal assemblies in concrete walls of subterranean vessels, such as catch basins of drainage systems, to provide a means for sealingly connecting discharge pipes to the subterranean vessels. A known method of casting involves mounting a coupler to a mandrel which is screwed or bolted to one of a pair of form walls used in casting a concrete wall. A metal reinforcing grid is then positioned between the form walls with the coupler and mandrel assembly extending through an opening through the grid. Newly mixed concrete is then poured into the form. While this is done, the mandrel supports the coupler to protect it against distortion or collapse under the heavy weight of the poured concrete. After the concrete solidifies, the form walls and attached mandrel are separated from the newly formed concrete wall with the coupler and grid embedded therein. The grid imparts strength to the concrete wall and the coupler permits a drainage pipe to be connected to the wall which is usually formed as part of a subterranean vessel. Known couplers or pipe seals which require the use of mandrels to be cast in concrete walls are disclosed in, for example, U.S. Pat. Nos. 4,951,914, 5,624,123, 5,711,536, 4,732,397 and 4,805,920.
A disadvantage associated with the use of a mandrel in casting a coupler in a concrete wall is that the mandrel location on the form wall dictates the location of the coupler in the concrete wall to be formed. If such location not desired, the mandrel must be unbolted and reattached to the form wall at a different location. The act of removing and reattaching the mandrel is time consuming and reduces the life of the form wall.
It is known to construct drainage systems using catch basins situated in various locations and having walls in which are embedded more couplers than are required for the particular application. This is to provide flexibility in structuring the drainage system to suit the needs of the particular application. The couplers used in such systems commonly include knock-out seal membranes which prevent liquid from flowing through the couplers when the couplers are not to be used. If the couplers are to be used, the seal membranes may be removed in whole or in part to provide openings through which similarly dimensioned pipes may be inserted. Thereafter, openings in the catch basin exist at the location of the couplers which have been thus modified. In some situations, such as when an underground drainage system is to be restructured to accommodate changing demands, there is a need to close previously formed openings in a catch basin.
It is therefore desirable to provide an improved coupler which can address the above needs and overcome the above disadvantages of prior couplers.
According to one aspect of the present Invention, there is provided a coupler for casting in a concrete wall of a subterranean vessel, the wall having a reinforcing grid, the coupler for coupling a pipe through an opening in the concrete wall and comprising a cylindrical wall having first and second ends, an inner surface, and an outer surface; and a plurality of circumferentially-spaced engagement members extending radially from the outer surface for engaging grid members of the reinforcing grid to mount the cylindrical wall to the reinforcing grid.
The coupler may include a circular transversely-extending seal membrane integrally formed with the inner surface across a longitudinally-extending passage of the cylindrical wall, the seal membrane having a circular portion which is removable to provide an aperture for slidably receiving a pipe therethrough.
The coupler may further include a removable support plug insertable into at least one of the ends, and being engageable with the inner surface of the cylindrical wall to provide radial support for the cylindrical wall during casting. The support plug may be adapted for use in sealing a longitudinally-extending passage of the cylindrical wall after the circular portion is removed, if desired.
The seal membrane may have a cylindrical flange integrally formed therewith about the circular portion to sealingly engage a pipe inserted through the cylindrical flange after removal of the circular portion.
According to a further aspect of the invention, there is provided a coupler for slidably receiving a pipe therethrough and for coupling the pipe to a subterranean vessel, the coupler being mountable to a reinforcing grid prior to the coupler and reinforcing grid being cast in a concrete wall of the subterranean vessel. The coupler comprises a cylindrical wall having a first end, a second end, an outer surface and an inner surface defining a passageway extending between the first and second ends for receiving the pipe. An end cap is releasably engaged to one of the first and second ends and has a sealing wall that is disposed across the passageway. A seal membrane is integrally formed with the inner surface and extends across the passageway, at least a portion of the seal membrane being breachable to facilitate insertion of a pipe through the passageway. The coupler may be cast into a concrete wall of a subterranean vessel with the first and second ends being exposed on respective opposite sides of the concrete wall.